Steam-boiler furnace.



PATENTED JAN. 6, 1903.

E. GIBSON. STEAM BOILER FURNACE. APPLICATION FILED EAR. 7, 1902.

K0 MODEL.

' INVENTOR 7 ATTORNEY WITNESSES ans l amas 0a.. PHDTO-LITHOU wuwuu UNITED STATES I PATENT OFFICE.

EDwAED GIBSON, E JERSEY CITY, NEW JERSEY.

STEAM-BOILER FURNACE.

SPECIFICATION forming part of Letters Patent N 0. 717,567, dated January 6, 1903.

Application filed March 7, 1902. Serial No. 97,088. (No model.)

To all whom it may concern.-

Be it known that I, EDWARD GIBSON, a citizen of'the United States, residing in Jersey City, in the county of Hudson and State of New Jersey, have invented a certain new and useful Improvement in Steam-Boiler Furnaces, of which the following is a specification;

It has long been recognized that in ordinary furnaces with any possible management of the fire a proportion of uncombined material flows away with the products of combustion and is lost. Many efforts have been made to reduce this evil by mingling air with the gases after they have risen from the bed of coal on the grate. To attain this, many modifications of the forms of the apparatus have been introduced with more or less success. been before provided for superheating air to be thus introduced and for dividing it into small streams and for controlling the flow.

There have been devices for attaining both these ends, but none quite satisfactory.

I have devised a construction and arrangement which ejects heated air to be mingled with the unconsumed gases in about the proportions found in practice to best promote complete combustion and tointroduce it while the gases are at a high temperature and as they are leaving the furnace. I introduce jets of air in a direction opposed to the flow of the gases. I have devised convenient means for very perfectly regulating the quantity of air thus introduced.

The following is a description of what I consider the best means of carrying out the invention.

The accompanyingdrawings form a part of this specification. I

Figure l is a central longitudinal section, certain parts being in elevation. Fig. 2 is a transverse vertical section on the irregular line 2 2 in Fig. 1. Fig. 3 is a plan view of certain portions removed; Fig. 1 is a corresponding section of a portion, showinga modification. Fig. 1 showing another modification.

Similar letters of reference indicate corresponding parts in all the figures where they appear.

. A is the boiler, and A the dome, from which the steam is taken through an ordinary pipe A A branch pipe 13, which may be of Means have lowed fire-bridge.

Fig. 4: is a section corresponding to smaller size, delivers a portion of the steam through a valve B and through a convoluted portion B of the branch pipe B, which is immersed in the uptake a, and thence through a continuation B past a controlling-valve B to be finally discharged through small perforations b in a tapering spiral or snail-formed coil B The violent flow through the properly-distributed perforations, dragging a large quantity of air with the superheated steam, produces the well-known effect of blowing in the ash-pit. This snail and the liberal airspaces between and around its convolutions are in an aperture in the wall of the furnace distinct from the door, so as to in no wise interfere with the ordinary uses of the door.

The thoroughly-dried and more or less superheated steam mingled with the air thus drawn in induces a pressureinthe ash-pit considerably above that which obtains in the furnace above the fuel. The bed of glowing coal, with varying proportions of ashes and cinder which obtain, according to the conditions of the fire from time to time, restrains the flow of the air and steam upward through the grates and makes it possible to deliver a strong series of jets from the properly-hol- The construction of the parts to efiect this and the direction and condition of the jets of air thus introduced will now be explained.

D D, &c. are smoothly-curved pipes of suitable material, as cast-iron, having trumpet ends arranged to gather in the ash-pit the air and steam under the pressure therein obtaining and lead it' away from the ash-pit up into a V hollow chamber e, formed by a series of hol the adjacent section, and forming a series of chambers along the top of the fire-bridge.

Perforations e are formed on the front side rial, each section is formed with a partition E having sufficiently liberal apertures 6 in passing through which the air, or rather the mingled hot air and steam, becomes further heated. The steam received through the snail B is first moderately superheated in its passage through the convoluted portion B of the pipe, and the mingled air and steam become further superheated by radiations downward from the fire into the ash-pit and by conduction through the brickwork and through the material of the curved pipes D. The shells E, from their position, are maintained at a high heat, and in circulating through they become further heated, this being gradually promoted by being restrained and compelled to flow through the apertures e in the partition E. This construction insures that with the fire in good condition the mingled air and steam issue in jets through the orifices e in a perfectly pure condition, ready to support combustion, and at a high temperature.

Another quality of importance results from my arrangement. The small streams ejected through the perforations e are inclined toward the front of the furnace. So far as their effect on the draft is concerned they retard it; but with any ordinary proportions of the parts and ordinary height and area of the chimney (not shown) there will be a sufficiently strong draft to allow of this slight restraint. By directing the jets so that they oppose the motion of the gaseous products of combustion I insure an unusually complete mingling of these gases. If there is, as usual, much combustible material unconsumed in the gases flowing away, the jets opposing the motion of the current contribute efficiently to induce further burning and complete combustion.

G G, &c., are valves corresponding in form and function to stove-dampers, but set with their axes vertical, as shown. On the shaft of each is an arm G, which is engaged by a line of links J, operated by an arm I on the shaft I, which shaft extends out through the furnace-front and is provided with a handle I, by which it may be turned at will. At certain periods, eminently in kindling the fire, these valves G should be turned into the tightly-closed position. Under ordinary conditions these valves may be Wide open, allowing much air to escape with strong force through the perforations 6 The valves may be set in any intermediate position desired.

Modifications may be made without departing from the principle or sacrificing the advantages of the invention. There may be an ordinary toothed arc and spring-dog to aid in holding the shaft I after it has been turned to any required degree; but the disturbing forces are slight, and I prefer to hold it simply by friction.

Parts can be used without others. I can dispense with the superheating-bends B of the pipe which brings the steam to the snail. I can with some success dispense with the entire pipe B and its connections, including the snail B In such case I dispense both with the blowing due thereto and also the mingling of superheated steam with the air. In this case the apparatus would use only natural draft, by which I mean the partial vacuum obtaining in the dues by the levity of the gases rising in the ordinary stack. (Not shown.) I can with some success use any ordinary means of blowing into the ash-pit. I can use the shells E reversedthat is, I can perforate the opposite sides of the shells E, so that their jets of highly-heated air and steam will be projected in the direction to favor the draft. Fig. 1 shows such modification.

There may be a smaller number of the sections E.

In applying my invention to those forms of boilers in which the gaseous products of combustion escape from the furnace laterally into the flue alongside, of which a common type is that known as the Lowe furnace, I should place my chamber 6 extending along at the side instead of the back. WhatIterm the bridge-wall is the boundary of the furnace, where the gases move from the furnace into the fines.

I claim as my invention- 1. In a steam-boiler furnace, a chamber e formed in sections matched together by interlocking vertical ridges in one engaging in corresponding Vertical grooves in the next, so as to be mutually sustaining and easily removable, and having small perforations 6 along the front face, in combination with the bridge-wall and with gently-curved pipes D embedded therein, arranged to lead air into the chamber at the full pressure obtaining in the ash-pit and to eject it in a direction opposed to the motion of the gases flowing from the furnace, and with the lip E extending over the perforations, all substantially as herein specified.

2. In a steam-boiler furnace a chamber 6 formed in sections matched together so as to be mutually sustaining and easily removable by a simple vertical movement and having small perforations along the front face, a lip above such perforations and one or more internal parts E formed integral therewith adapted to conduct heat downward from the heated top and impart it to the gaseous fluid, in combination with the bridge-wall and with gently-curved pipes'D embedded therein arranged to lead air into each chamber at the full pressure obtaining in the ash-pit and to eject it in a direction opposed to the motion of the gases flowing from the furnace, all substantially as herein specified.

3. In a steam-boiler furnace, a transverse chamber 6 formed in sections matched together so as to be mutually sustaining and easily removable. by a simple vertical movement and having small perforationsalong the front face, in combination with the bridgewall and with gently-curved pipes D embedded therein arranged to lead air into the chamber at the full pressure obtaining in the ash-pit and to eject it in a direction opposed to the motion of the gases flowing from the furnace and with easily-turning oscillatable' valves G one in each passage and connections thereto from a single handle I at the front so that the effect can be reduced or entirely suppressed at will, all substantially as herein specified.

4:. In a steam-boiler furnace a chamber 6 formed in sections matched together so as to be mutually sustaining and easily removable by a simple vertical movement and having small perforations along the front face, the 

